The prior art is aware of the typical handheld syringe which is used by the general population for withdrawing blood and the like for sampling purposes. Generally, these syringes include a cylinder, a piston disposed therein, a piston rod secured to said piston and extending outwardly of one end of said cylinder and terminating in a handle for controlling movement of the same, and a hollow needle extending from the other. In use, the needle point is introduced into the body from which the fluid sample is to be withdrawn and held thereat by grasping the cylinder with one hand and simultaneously pulling on the handle means with the other hand to control a vacuum to withdraw the fluid from the body through the hollow needle into the cylinder. Thereafter the fluid sample is used, or processed, in the normal fashion.
It is apparent then that the major drawback associated with conventional syringes is the fact that it is a two-handed process which increases the pain, increases the chance of needle trauma to the vessel wall, increases the chance of accidental puncturing of the vein with its associated bleeding and the inflammation of the vein.
It is the object of the present invention to provide a new one-handed operated syringe which will obviate the deficiencies of the conventional syringe enumerated hereinabove. In a search of the prior art in the U.S. Patent Office, Russian Pat. No. 445,411 discloses a syringe of the same general type as applicants.